He says these middlemen don't have to disclose what rebates they receive from drug companies, and some have unfairly pocketed some of the savings that should have been passed on to the consumer.

He says rebate information should be public.

"We want to look under the hood, quite frankly," says Wood. "If you're trying to hide something then I think that people outta know that. We want to make sure that consumers are getting what they hope they're getting through their plan. But the purchaser ought to be able to verify that they're actually getting what they're paying for. And right now, there's a big question of whether that's happening."

Representatives of some middlemen opposed to the bill say disclosing this information would hurt price negotiations.

Another bill calls for drug makers themselves to let providers know before they make a significant raise in drug pricing.

Sally Schilling is a Davis native and a graduate of the UC Berkeley Graduate School of Journalism. She has reported on redwood poachers robbing national forests in Humboldt County and the dangers of melting tropical glaciers in the Peruvian Andes. Read Full Bio